


An Unlikely Partnership

by owlmoose



Category: Iron Man (Movies), Sherlock Holmes (Downey films)
Genre: Alternate Universe - Fusion, Alternate Universe - Steampunk, Canon-Typical Violence, Community: trope_bingo, Crossover, Doppelganger, Gen, Things that seemed like a good idea at the time
Language: English
Status: In-Progress
Published: 2013-04-28
Updated: 2013-04-28
Packaged: 2017-12-09 20:58:41
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,850
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/777919
Author URL: https://archiveofourown.org/users/owlmoose/pseuds/owlmoose
Summary: <blockquote class="userstuff">
              <p>Taken prisoner by a gang in Afghanistan, John Watson encounters a surprise among his fellow captives: Sherlock Holmes. Except it isn't Holmes, but American industrialist Anthony Stark, a very different man who happens to have the same face. The story of their escape, and what followed.</p>
            </blockquote>





	An Unlikely Partnership

**Author's Note:**

> Work in progress. Pairings and characters to be added as the story moves forward, and the rating may change. Written for Trope Bingo, to the prompt "doppleganger + fusion".

Somehow, John Watson had fallen asleep despite the lumpy pile of sacks that served as his bed, the rough road, the pains shooting up his leg. When the wagon stopped, he jolted awake, seconds before rough hands grabbed him and pulled him out of darkness into blinding light, then back into the dark before he had time to do more than blink.

His captors pushed him along, forcing him to move despite the agony in every step, shoving him into the back of what he dimly registered as a cave. Then a door slammed behind him; he tried to turn around, to run, but the leg gave way under his pivot, and he collapsed to the rocky, dusty floor, breathing heavily. Where was he? What on earth was going on?

"You, hey you!" A voice cut through the haze of exhaustion and pain, and John looked up, head falling back on his tired neck. "Are you the doctor I sent for?"

John grabbed the edge of a table and pulled himself to his feet, putting all his weight on the left leg. "I am a doctor, although I didn't know I'd been sent for." Although that explained why the Afghani soldier who'd pulled him off the field had become so excited at the sight of his medic armband, and why he'd been dragged off to the wagon rather than rounded up with the other prisoners.

"Well, come here, then, and assist me." It was a man, of early middle years, wearing spectacles and a frown; he spoke with a slight accent, possibly Persian.

"I would, but…" John tried to take a step forward, then grimaced as fresh agony lanced through his calf. "I don't know how much use I'll be in this state."

"You need to try, or this man will die." John could hear the weariness in the speaker's voice. "Please. I beg you to help me."

John gritted his teeth and pulled himself around the table to where the man stood. "I-- don't know how long I can keep to my feet. But I will do my best."

"What's wrong?" The man moved quickly forward, kneeling at John's feet, then whistled. "That's a nasty cut you have there. Bayonet?" John nodded. "Well. We don't have much time, but you'll be more use to me if you can stand. Shall I clean and bind it for you?"

"That would be capital," John admitted. "I-- ahh!" He gasped as the man ripped his trouser leg open and dabbed at the wound with alcohol, the burning sensation driving out any residue of his exhaustion.

"Sorry, sorry, best to get it over with." The man finished the cleaning job quickly, then held his hand out. "Bandages? They're on the table beside you." John found the roll and tossed it into the other man's waiting palm, then leaned back against the table, biting his lip as the cloth was wound around his leg. Once finished, he tested it, and let out a breath of relief. It still hurt, but at least it would take more of his weight. 

"Much better," John said. "You have my thanks."

"You can repay me by saving this man's life," the medic said, leading John to a stretcher, propped up between two rocks, where someone lay. John could hear his moaning now, and he took a few short steps, before stopping dead his first sight of the man's face.

"What the devil? Holmes?!" He rushed to the patient's side, heart beating faster. Holmes, in Afghanistan? Dying of gunshot wounds to the heart? How was this possible?

The other man took a place across the stretcher, shaking his head. "His name is not Holmes."

John stared down at the patient. Under the beard, the mustache, the blood and dirt and sheen of unhealthy sweat, still it was a face he knew nearly as well as his own. "No," he said, "no, this is Sherlock Holmes. I would stake my life on it."

"I tell you, it is not. He is Anthony Stark, an American military consultant. And he will be dead soon if we do not act!"

John looked over the man again -- Holmes, not-Holmes, the wound in his chest was seeping blood at an alarming rate. "You're right," he said. He caught the man's eye. "If we are to work together, I need a name."

"Yinsen," he said, holding out a hand. "Doctor and engineer, trained in London, most recently of a village near here."

John took it for a quick shake. "Captain John Watson, MD, Her Majesty's Armies." He stepped back and rolled up his sleeves. "Now, tell me the situation."

-x-

Tony Stark woke in a quiet room -- too quiet. The last thing he'd known was a world of swirling chaos as Afghani hordes overran the camp where he'd been the guest of honor: gunfire, bombs exploding, soldiers shouting and grunting and screaming in pain. The battle, then, was over, and he had survived, but why didn't this sound like a hospital? All he could hear was the soft murmuring of two male voices, without the echo and background bustle he would have expected. Why was it so dark? Why was his whole body sore? What was this weight on his chest?

He tried to take a deep breath, but it came out as more of a gasp. As he opened his eyes, he had to stifle a fresh scream from his still-raw throat. "What-- what is that-- where am--"

A hand fell on his shoulder, with a pressure that was somehow firm and gentle at the same time. "Relax, Mr. Stark." It was a male voice, British and authoritative. "You were grievously wounded in battle, but we patched you up. Try not to move around too much."

Tony tried to shake free of the man's grip, but he couldn't, not with that giant… thing weighing him down. "What in the hell is that contraption?"

"I'm not really the best person to answer that question," the man replied. "The most I can tell you is that it's some kind of magnet, and that it's keeping you alive. So please don't struggle too much -- you might knock it out of place." He lifted his hand and moved around to the side of the bed, kneeling down so that Tony could see his face. "My name is Dr. John Watson, and I was brought here to help you."

Even in the dim light, Tony could sense Dr. Watson's sincerity. "And where is 'here', exactly?"

"A cave in the mountains, somewhere." Watson grimaced. "I'm afraid I don't have any more specifics -- they didn't allow me to admire the scenery on the way. And I know very little about our captors. For that, I would suggest you apply to Dr. Yinsen." He stood up with a glance over his shoulder and waved at someone. Another man came into focus: shorter, wearing glasses and a beard.

"Good morning, Mr. Stark," the second man said with a quick bow. His accent was vaguely English, vaguely Middle Eastern. "I'm sure you have many questions, and I plan to answer them, but I'd like you to try and sit up first. Carefully, if you please."

The weight on Tony's chest lessened as the man moved the large metal box off to the right; Tony could see it was still attached to him via a tangle of cables and tubes, but he couldn't quite see how. He wanted to argue, but he didn't dare, not before he had more information. So instead, he obeyed, lifting himself up onto his elbows, and discovered a large metal disk, larger than his fist, that seemed to be attached to his body.

"All right." Tony gulped, then took a deep breath. "I'm going to ask one more time, and after that I'm going to get testy. What is that thing, and why have you implanted it in my chest?"

"It's an electromagnet, and it's there to allow your heart to continue beating," Yinsen said calmly. "When your camp was attacked, you took a chest full of steel pellets. I was able to remove most of them, but others were too close to your heart for me to risk taking them out." He tapped the metal disk, and Tony winced under the vibrations. "This magnet is keeping them from becoming more deeply lodged."

"Hmm." Tony turned his head and nodded at the machinery on the table. "And I suppose that's the steam engine keeping the magnet energized?"

"Correct!" Yinsen smiled. "I see the renowned intellect of Anthony Stark remains intact."

Tony frowned. "It's not very portable." He looked around the cave, taking in the piles of metal plates and engine parts, and his mind started working. "But maybe I can fix that. What's all this?"

"All this," Yinsen said, sweeping his arm around the cave to indicate the piles of metal and machine parts, "are the components to build war machines. Your machines, Mr. Stark. The ones you sold to the British government, now in the hands of their enemies. And very soon, I think, you will find out what they want from them, and from you."

"Yes, well, we'll see about that." Tony swung his legs around the side of the bed and peered at the stacks of gears, pumps, and metal casings. "I'd say my priorities are a little bit different. Dr. Watson, if you would assist me? I can't go wandering through the piles, but I can tell you what to look for."

"Of course." Watson got to his feet. "What will you be building?"

"Call it an exercise in miniaturization," Tony said. "Once that's done and I'm mobile again, we can talk about our next step: getting the hell out of here."

-x-

The next few days passed at a breakneck pace that felt all too familiar.

Anthony Stark was not Sherlock Holmes; his American accent, his passionate nature, and his quick wit proved that fact to John's satisfaction within the first few hours. In other ways, however, John could have been back in the flat at 221B, aiding Holmes in one of his mad research projects: the fascination with arcane bits of technology, his swift and nearly impenetrable brain, his tendency to work through the night on almost no sleep, the absolute concentration with which he attacked every task. Now, three days later, he was concentrating very closely indeed, welding together what looked to be a miniature steam engine, smaller than John's fist. John leaned against the edge of the table to take the weight off his ankle and took a closer look. "You will use that to power the electromagnet?" he asked.

"That's the idea," Stark said, not pausing in his work. "Although it will produce a lot more power than I need just to run the magnet. The rest… that's what we'll use to bust our way out of here." He glanced at the pile of armor and guns in the corner. "If those Ten Rings goons think I'm going to use these materials to build them tanks, they have another think coming."

John nodded; on the first morning here, they had received a visit from the Afghani officer who had taken them captive, leader of a splinter group that Yinsen called the Ten Rings. He had, via Yinsen's translation, explained that Stark had been brought here to assemble a vehicle out of the metal plates, machine guns, and engine pieces that were scattered all over the cave. John had seen one of these monstrosities from a distance -- the other soldiers had called it an "armored tractor car", but Stark's term, "tank", was more colorful. Stark had agreed to the man's face, then immediately returned to his original project. "So then, what will you build?"

Stark put the finishing touches on a connection, then stretched backwards with a groan. "That's an excellent question, Dr. Watson." He set the tiny engine aside, then pulled out his notebook and opened it on the table, to show what looked like a suit of armor. "Something like a tank, but instead of being built on the skeleton of an automobile, it will have a much more finely tuned machine at its base. Namely, me."

From his spot across the table, where he was keeping watch on Stark and the door in equal parts, Yinsen leaned over the plans. "Interesting," he said. "And what will you do with this… human tank?"

"First, I take care of these miscreants holding us," said Stark. "Then I get us back to civilization."

Yinsen shook his head. "How things change. This place, my people, we were once the cradle of civilization. Now we are torn to pieces by war, and whose war?" He looked at John, then Stark, a flash of anger in his eyes, and then he turned away. Stark stared at him for a moment before returning to his work, and John settled back in his seat and tried to ignore the pain in his leg. 

-x-

"Ready?" Tony stood up and took a few heavy steps over to the rig he had built to hold the chestpiece and helmet of his plated armor suit -- he had already buckled the foot and leg coverings into place, and the gauntlets, heavy with machine guns, waited on a nearby table.

"Ready," Watson replied, and across from them, Yinsen nodded.

"All right. Let's get this show on the road." Tony lifted his arms up over his head, and Watson and Yinsen maneuvered the amor into place, lowering it to rest his shoulders, then connecting the tubes to the connectors on the steam engine embedded in his chest, setting the circuits that would power his arms, legs, and weapons. Then each man took one arm piece and slid them over his hands. Tony tested the elbows, bending them, checking his shoulders and each knee. It was heavy and awkward, but it would work. He fitted his fingers into the triggers for the guns, then relaxed them. "Now once these last few connectors are ready--"

He was interrupted by a pounding at the door -- the door that Yinsen had braced shut with boxes and a crowbar -- and the sounds of shouting in Persian. Yinsen called something back, then turned to Tony and John with a grim head shake. "I told them to wait, but they are not listening. We will need--" The pounding became a series of crashes, the doors buckling under the onslaught.

"Come on, hurry it up," Tony said, fingers twitching. "If we can just get these connections finished…"

Yinsen lowered his eyes. "There is no time! But I will go buy you some." And before Tony or Watson could voice an objection, he grabbed two of the spare guns off the table and ran out the door, his howl followed by a smattering of gunfire as the door fell shut behind him.

Tony could only stare, open-mouthed, while Watson snapped the last of the connections into place and closed the chest plate. By the time he finished, the sound of gunfire had receded. Maybe Yinsen had cleared the Afghanis out, then found a place to hide. "Your helm," Watson said, lowering it over Tony's head. At first everything turned back, and then Watson twisted the helmet sideways to put the eyeholes in the right place and secure the fastenings. "Can you see?"

"Straight forward, yes," Tony said, blinking a few times, looking side to side. "But my peripheral vision is all but useless."

"I'll have to be your side view, then." Watson took the last gun from the table, loaded it, and stuck it in his jacket pocket. "Are you ready?"

Pushing away the sound of gunfire -- was it getting more distant? Longer breaks between salvos? -- along with his worries about Yinsen, Tony checked all his connections once again -- now that the steam engine supplied power to the joints, he found it much easier to move. "As I'll ever be," he responded. "Time to get out of here." He stepped forward, the weight of the armor pulling him free from the scaffolding, the metal tubes groaning as they snapped in half. Watson had already cleared the path from the rack to the doorway, and so Tony was able to walk straight forward, he reached the door in a dozen crashing steps, the ring of metal against stone. Meanwhile, Watson tossed aside the last of the debris they'd used to brace the door.

"Let's go," he said, pushing the door open. "I'll be right behind you."

Tony tried to nod and failed -- I wonder if I could articulate the neck better? -- then wasted no more time in setting off down the hallway, walking as briskly as he could. He found it surprisingly easy; the electrical power being generated by the engine more than counteracted the weight of the armor, allowing him to move almost normally. Just with a hell of a lot more noise. The armor rattled and clanged with each step, and as he walked Tony considered the possibilities to dampen the sound. Perhaps by incorporating rubber into the joints. But he had to shove aside the images of elegant designs as he stepped around a corner, confronted by men in a mix of robes and military uniforms, not to mention at least a dozen guns pointed straight at his head.

"Stop, now!" one of the men shouted.

"I don't think so," Tony replied, and he swung his left arm around, squeezing the trigger under his index finger to fire, spraying the crowd with bullets. Some men screamed and fell; others fired back, and Tony had to brace himself as his chestpiece and helmet were struck by the tiny projectiles, pushing him first left, then right. None of them were strong enough to pierce his armor or knock him over, however, and he fired into the crowd again, using his right arm this time.

That was enough to break the human barrier. The soldiers who were not wounded broke and ran, presumably falling back to another position; Tony kept firing, and a few more fell before the last stumbled around the corner. Tony started to follow again, but he was stopped by a shout from Watson.

"Stark! I found Yinsen-- oh, God." 

Tony turned, an awkward proposition with the suit, and then he saw Yinsen, sprawled out over a pile of boxes. Even through the small eye slits of his mask, hampered by the dim light of the cave, Tony could tell that his chest was a ruin of blood and bullet holes, and the blood drained from his face. "No," he said, at first hushed, and then his voice rose in desperation. "No, no, we have to get you out of here!"

Watson knelt on the ground next to Yinsen, his hand wrapped around Yinsen's wrist, then resting against his neck. He lowered his head. "It's too late, Stark. He's too far gone."

"But… you're a doctor. There must be something you can do! He saved my life, I can't-- I can't just leave him here."

Yinsen shook his head from side to side, weakly. "It's all right, Anthony. I-- expected this. I am ready. Now go, please. Take your life and use it for something… something…" He coughed, then spasmed, once, before falling back down against the crates. Watson checked for a pulse one last time, then lifted a palm to his face to close his eyes. Then he got to his feet and faced Tony, who couldn't move.

"He's gone. He sacrificed his life to get us out of here. Let's not waste the chance he gave us."

"Right." Tony forced himself to look away from Yinsen's corpse, to face Watson instead. "Get behind me, and let me know if anyone's coming up on my blind sides."

"Understood."

-x-

Stark lifted his head high and turned to march down the hallway, squealing and clanking all the way. John took up his place a few steps behind him -- close enough to use the bulky metal man as a shield, but with enough distance that he could see potential ambushers lurking in the shadows of the cavern. Stark's armor was impressive, a fearsome machine, a wonder that he could even walk in such a contraption. For the hundredth time, he wondered what Holmes would make of all this. Well, if they got out of here, maybe Holmes would have the chance to examine it for himself, even if the idea of Stark and Holmes in the same room made John's head spin a little. 

But first they would have to make good on this escape plan, such as it was. John was uncertain whether Stark had thought the plan much through besides "have a bigger and better weapon than their opponents". The human tank would get them away from their captors and the cave, almost certainly, but beyond the cave and back to the army encampment? About that, John was less sure. His leg was healing, but still sore; he doubted he could walk all the way back across the lines. But he could not spent time wrestling with doubts, not when Afghanis might lurk in every corner. 

Like that one, popping out from behind a pillar on the right; "Look out!" he shouted, and then he had his pistol out, firing around from behind Stark to catch the enemy in the throat. Stark pivoted, turning at the waist to pepper the area with bullets, just in case any others were hidden in the shadows, and they were rewarded with a muffled scream. A few steps more had them rounding another corner, and they encountered another door, this one likely braced shut on the other side. Stark pounded at it with a metal fist, but it didn't budge. "No good," he said. "I'll have to kick through. Stand back!" John stepped back as Stark turned sideways, braced all his weight on his left leg, and focused the power of the engine into the right to kick the doors open. The wood shattered beneath the blow, splinters flying everywhere, including one large shard hurtling straight at John's head. He ducked and fell into a crouch, dropping his gun to covering his face with his hands and bending over to protect himself from the worst of the debris. Then he stood and shook himself out, brushing small bits of wood and metal out of his hair.

Stark at turned again, to face him now. "Sorry," he said, true contrition in his voice. Watson just shook his head.

"I'm fine." He retrieved the pistol from the floor and gestured forward with it. "How much further, do you know?"

"Yinsen said one more door after this one." Stark paused, as though he were checking a map that he carried in his head. "Down this corridor, then turn right, and we should be out of here. But from here on out we'll need to watch the back as well as the front. Think you can take care of that for me?"

"That's why I'm here, isn't it?" Watson reloaded his pistol and patted his backup. "Now let's keep moving." 

"Whatever you say, Doctor Watson." Stark shouldered his way through the ruins of the door, clearing as much of the debris as he could, and John walked behind him, picking his way over the pile of kindling that remained. As they made their way through the cave system, John was continuously on watch: eyes forward, sweeping left and right, checking back over his shoulder every few seconds. It seemed forever, but in reality it was only a few minutes before they reached the turn, fighting their way past only one pocket of resistance and one small ambush from behind, until they reached the final set of double doors, which stood open, yellow afternoon sunshine spilling onto the floor.

"A trap?" John suggested. 

"Probably," Stark replied. "But I don't see as we have much choice."

"I suppose you're right." John stepped around Stark's armor. "Let me scout it out first." He sidled up the hallway to one of the open doors, then crouched behind it, letting his eyes get used to the first sunlight he'd seen in days. While there, he examined the doors -- they were metal, and heavy, and would have been nearly impossible to break through. Either the rest of the Ten Rings gang had fled in a hurry, or they had, indeed, laid a trap, if a fairly obvious one. Once he felt confident that he could see in daylight, John peered around the door, staying as far back in the shadows as he could and took stock of the situation. 

Fifteen men, at least, had set up barricades, all of them armed with machine guns that were aimed at the door. And one more, manning a cannon, also aimed at the door. John slipped back into the darkness. "They're waiting," he said. "And they have a cannon."

"I guess that shouldn't be a surprise. I'll have to see about working one of those into the next model." Stark checked that his arm guns were primed and ready. "For now, we go with what we've got."

"Right. Fortunately it's one of the slower, older ones. I imagine it will be primed to fire as soon as we emerge, but once they've used that shot it will take them some time to prepare the next."

"Ah." Stark paused for a moment. "Okay. I can work with that. Are you ready?"

John reloaded his pistols -- only a few more bullets remaining, so he would have to make each shot count -- and then checked Stark's supply of ammunition, which consisted of several rolls of ammunition tape, balanced on his back. "I suppose."

"Keep back until the cannon fire is clear. Then be ready to move on my signal." Without waiting for confirmation, Stark charged forward, through the door, arms wide but not firing. He stood in the door, as though he were bracing for the first volley, which came immediately, a barrage of bullets followed by the booming report of the cannon. At that moment, Stark flung one of the metal doors shut and got behind it, blocking the cannon fire with the rebels' own doors. 

Stark stepped out from behind the closed door and raised his weapons. "Our turn," he said, and opened fire, concentrating on the men frantically working to reload the cannon. John took that as his signal and stepped out from behind Stark's armor, taking advantage of the confusion to pick his own targets, felling four men from the barricades, then pulling his second pistol to take down two more. Then he felt it: a searing pain in his calf. He went down, grasping at the wound.

"John?!"

"I'll-- be okay," John gritted out. It was only half a lie, he decided as he examined the new wound. It wasn't bleeding much, but the bullet was lodged too deep for him to remove here -- he could feel it, scraping at the bone. He doubted whether he could put any weight on it. After scrambling behind Stark's left leg for cover, he peeked around to check the battlefield again. He and Stark had made a dent in the enemy force, to be certain. But for each man that fell, two more swarmed out of the barracks to replace them, and John began to doubt whether Stark's armor would be enough. 

"Stark! Reinforcements!"

"I see them," Stark shouted back. "Tell me, does that look like a dynamite stockpile to you?" 

John followed his gesture: he pointed at a pile of barrels and crates next to the canon. "I'd say that's likely, yes."

"Then stay down!" Stark turned both his weapons on the pile of explosives, firing into them until his ammunition was almost spent. 

For a moment, it seemed as if nothing would happen, and then one box caught fire, followed by a second, and John looked away just in time, covering his face as the dynamite exploded, heralded by screams and the whistling sound of debris flying through the air. He turned his head to the side and risked a look, just in time to see a giant metal tube fall from the sky and land less than a foot away with a loud clunk. "Is that the cannon?"

"Part of it," Stark said, his voice oddly chipper. "C'mon, I think we can get out now, while they try to regroup."

"You can," said John, with a mournful look at his bloody, aching leg. "I'm done with walking, I fear."

"Who said we needed to walk?" Stark turned around and lifted John up into his arms. "Grab my neck," he said, and John complied as Stark cradled him in the crook of his left arm. Then Stark twitched his right fingers a few times, and the metal around his feeet twisted up and around the boots, forming into chains very similar to the treads the tanks used instead of wheels. "Hold on tight." And then they shot forward, hurtling down the stairs, past the few surviving enemy soldiers, and over the sands into the sunset.


End file.
